Remove Event.relatedTargetScoped and update event path calculation for relatedTarget

third_party/WebKit/LayoutTests/shadow-dom/event-composed.html

Index: third_party/WebKit/LayoutTests/shadow-dom/event-composed.html
diff --git a/third_party/WebKit/LayoutTests/shadow-dom/event-composed.html b/third_party/WebKit/LayoutTests/shadow-dom/event-composed.html
index 891b684ea93d8dc2a2fccf5b07ce8e8a33f8be97..48a98d5023ef17e3f6835181aa2b62c0bec3591b 100644
--- a/third_party/WebKit/LayoutTests/shadow-dom/event-composed.html
+++ b/third_party/WebKit/LayoutTests/shadow-dom/event-composed.html
@@ -8,15 +8,6 @@
   </template>
 </div>
 <script>
-function assert_event_path_equals(actual, expected) {
-  assert_equals(actual.length, expected.length);
-  for (let i = 0; i < actual.length; ++i) {
-    assert_equals(actual[i][0], expected[i][0], 'currentTarget at ' + i + ' should be same');
-    assert_equals(actual[i][1], expected[i][1], 'relatedTarget at ' + i + ' should be same');
-    assert_array_equals(actual[i][2], expected[i][2], 'composedPath at ' + i + ' should be same');
-  }
-}
-
 test(() => {
   const e = new Event('test');
   assert_equals(e.composed, false);